Railway track tamping apparatus



p 1967 J. K. STEWART RAILWAY TRACK TAMPING APPARATUS Filed July 25, 1966 m m m m w m\, m m\ w L MM x W I m kw .11. 1! 1|. w 1' w w a l v 0 co n Ho nw m m 1 mi i m um h M O w sa 3 w :4 hr Jr 5 f United States Patent Ofiice 3,343,497 Patented Sept. 26, 1967 3,343,497 RAILWAY TRACK TAMPING APPARATUS John K. Stewart, Dorva], Quebec, Canada, assignor to Canada Iron Foundries, Limited, Montreal, Quebec,

Canada Filed July 25, 1966, Ser. No. 567,637 Claims priority, application Great Britain, July 28, 1965, 32,329/65 5 Claims. (Cl. 104-12) This invention relates to tamping devices for tamping the ballast beneath the ties of railroad tracks.

One of the great problems with railroad maintenance vehicles is their rate of production. Because of the limited amount of on track time which railroad maintenance devices have in a normal working shift, it is important that as much as possible be accomplished during that time. It will be readily appreciated that on busy track, maintenance devices have to be removed frequently from the track to permit the passage of traffic and slow production rate, coupled with frequent breaks to clear the track, leads to the requirement of a very long and careful work plan schedule in order to accomplish a maintenance program.

The art has been striving for many years to increase the production rate of maintenance vehicles, particularly tamping vehicles, for example it has been proposed to provide two tamping cars, one tamping the odd ties and one tamping the even ties, and it has been proposed to provide two sets of tamping heads on one vehicle so that one tamping head will tamp odd ties and the other tamping head will tamp even ties.

The present invention seeks to further increase the productivity of tamping vehicles by providing a tamping device mounted on a railroad vehicle for movement along the track, which tamping device comprises at least two pairs of tamping units arranged on the vehicle longitudinally of the track, all units being substantially in line with one another, each unit of each pair being spaced apart longitudinally of the track so as to span a tie therebetween; and the unit of one pair adjacent the unit of the other pair being spaced apart longitudinally of the track so as to span a tie therebetween; squeezing means for pivoting each unit of each pair towards the other unit of its pair and for pivoting the said adjacent units towards each other, whereby, in operation to impart a squeezing action to the ballast beneath the ties between each pair and to the tie between said adjacent units.

Preferably squeezing means for pivoting each unit of each pair towards the other unit of its pair comprises a hydraulic piston and cylinder arrangement.

The following is a description by way of example of one embodiment of the invention reference being had to the accompanying drawings in which:

FIGURE 1 is a schematic reproduction of a side view of a tamping device in accordance with the present invention; and

FIGURE 2 is a detail plan view partially in section.

Referring to the drawings, a railroad tamping vehicle V mounted on wheels W carries at the front thereof a tamping head comprising two pairs of tamping units for each rail of the track. Each tamping unit is essentially the same as the tamping units described in my Canadian Patent No. 646,048 and comprises an electric motor 11 driving a depending crankshaft 12 (FIGURE 2), which through connecting rods 13 and rocker arms 14, oscillate the fork arms 15 of the tamping units at low amplitude high frequency, whereby to vibrate the ballast B when in contact therewith.

The tamping units are each mounted for pivotal movement about a vertical axis in collars 17. The collars are attached by pivot pins P to bifurcated arms 19 of frames 20 so that the units are mounted in pairs for towardsand-away swinging action about pivot pins P and for up and down reciprocation in frames 20 along masts 24. The reciprocating action may suitably be provided by hydraulic means in conventional fashion.

Hydraulic piston and cylinder arrangement 26, 26' are provided between each unit of each pair, the piston rod 27 of each arrangement being attached through a swivel bearing 28 to an inverted U shaped yoke 29 of a squeeze frame 30 secured to the unit 10, while the piston 31 of the arrangement is attached through swivel bearing 33 to a similar shaped yoke 35, secured to the other units of the pairs.

Hydraulic piston and cylinder arrangement 26 imparts a towards-and-away squeezing action to the tamping units W, X of one pair about their pivot pins P, whilst arrangement 26' imparts a towards-and-away squeezing action to the units Y, Z of the other pair. The collars 17 provide for universal pivoting ofthe units during tamping whereby to compensate the tamping action of the pair beneath a tie T if one of the forks 15 of one tamping unit should encounter a snag. Stops S on stop bars 28 projecting outwardly of frames 20 limit the towards-and-away movement of the tamping units by contacting the yokes 29, 35.

The piston and cylinder arrangements 26, 26' also provide for a towards-and-away squeezing action between the unit X of the first pair of tamping units adjacent to the unit Y of the outer pair of tamping units.

Quite clearly yet a further pair of tamping units, or indeed two further pairs of tamping units, depending upon the practicability of the arrangement, could be employed in series if desired.

In operation one pair of tamping units W, X are lowered on its frame 20 into the ballast on either side of the tie A which lies between them and the other pair of tamping units Y and Z are simultaneously lowered into the ballast to span the tie C between them. On the first squeezing operation the units W, X and the units Y, Z squeeze together in paiis simultaneously under the action of the piston and cylinder arrangements 26, 26 to consolidate the ballast beneath the ties A and C. Then on the second squeezing operation and without withdrawing any of the tamping units from the ballast, the tamping units X and Y are squeezed together (as shown in phantom in FIGURE 1) by the combined action of the arrangements 26, 26 to consolidate the ballast beneath the tie B. During the second squeezing operation of the tamping units X and Y, the tamping units Z and W move up against the inner stop S on stop bars 38 and remain there until the squeezing operation on the tie B has been completed. Alternatively, in order to completely stop the movement of the tamping units W and Z during the squeezing operation of the units X and Y on the tie B, an auxiliary stop may be inserted between the inner stop S on the top bar 38 and the yoke 29 on initial movement of the units X and Y towards the tie B and be removed therefrom when they reach the tie B. In this manner the production capacity can be improved very considerably since the time taken to lower the pairs of tamping units into the ballasts and to withdraw them from the ballast after a tamping operation does not have to be repeated for the operation of tamping of the tie B by the tamping units X and Y.

The tamping units X and Y while being withdrawn from the ballast are returned to a central position, unit X between ties A and B and unit Y between ties B and C.

It is to be understood of course that the operation could be reversed, that is after lowering the tamping units into the ballast, tie B could be tamped first by tamping units X and Y and ties A and C subsequently and simultaneously tamped by their respective pairs of units. Still further of course if the advantages of the invention are not to be obtained, the device could be operated in more conventional fashion and the pair of tamping units W and X could tamp tie A simultaneously with the tamping of tie C by the units Y and Z and then the tamping vehicle could move to the right on withdrawal of the tamping units, which could again be lowered so that pair W, X could tamp tie B and pair Y, Z could tamp tie D.

In order to allow for differences in tie spacing at least one pair of tamping units, say, W, X,could be made longitudinally adjustable in the vehicle frame.

It will be appreciated that, whilst in the drawings, only the tamping heads over the inner side rail have been illustrated for clarity, the tamping heads will be duplicated on the other side of the vehicle over the other rail of the track.

What I claim as my invention is:

1. A railroad tamping device mounted on a railroad vehicle for movement along the track, which tamping device comprises at least two pairs of tamping units arranged on the vehicle longitudinally of the track, each unit of each pair being spaced apart longitudinally of the track so as to span a tie therebetween and the unit of one pair adjacent the unit of the other pair being spaced apart longitudinally of the track so as to span a tie therebetween; squeezing means for pivoting each unit of each pair towards and away from the other unit of its pair and for pivoting the said adjacent units towards and away from each other whereby, in operation to impart a squeezing action to the ballast beneath the ties between each pair and to the tie between said adjacent units. 7

2. Apparatus as claimed in claim 1 in which the squeezing means for pivoting each unit of each pair 30 towards and away from the other unit of its pair comprises a hydraulic piston and cylinder arrangement.

3. Apparatus as claimed in claim 1 in which each tamping head comprises a pair of tamping units pivotally mounted on collars attached to a frame for vertical reciprocation relative to the track; yoke members extending from said tamping units; a hydraulic piston and cylinder arrangement connected on the one hand to the yoke of one unit and on the other hand to the yoke of the other unit and adapted on operation to pivot the tamping units towards and away from each other to provide a tamping operation on a tie between the tamping units, and means adapted to limit the pivotal movement of the units.

4. A method of tamping a railway track comprising tamping first and third ties with first and second tamping heads and thereafter tamping a second tie between said first and third ties using part of said first tamping head and part of said second tamping head.

5. A method of tamping railroad track comprising tamping an intermediate tie utilizing a unit of a first tamping head and a unit of a second tamping head and thereafter tamping the tie immediately adjacent and on one,

side of said first mentioned tie by a first tamping head, and tamping a further tie immediately adjacent and on the other side of first mentioned tie with a second tamping FOREIGN PATENTS 205,532 10/1959 Germany.

ARTHUR L. LA POINT, Primary Examiner. R. A. BERTSCH, Assistant Examiner. 

1. A RAILROAD TAMPING DEVICE MOUNTED ON A RAILROAD VEHICLE FOR MOVEMENT ALONG THE TRACK, WHICH TAMPING DEVICE COMPRISES AT LEAST TWO PAIRS OF TAMPING UNITS ARRANGED ON THE VEHICLE LONGITUDINALLY OF THE TRACK, EACH UNIT OF EACH PAIR BEING SPACED APART LONGITUDINALLY OF THE TRACK SO AS TO SPAN A TIE THEREBETWEEN AND THE UNIT OF ONE PAIR ADJACENT THE UNIT OF THE OTHER PAIR BEING SPACED APART LONGITUDINALLY OF THE TRACK SO AS TO SPAN A TIE THEREBETWEEN; SQUEEZING MEANS FOR PIVOTING EACH UNIT OF EACH PAIR TOWARDS AND AWAY FROM THE OTHER UNIT OF ITS PAIR AND FOR PIVOTING THE SAID ADJACENT UNITS TOWARDS AND AWAY FROM EACH OTHER WHEREBY, IN OPERATION TO IMPART A SQUEEZING ACTION TO THE BALLAST BENEATH THE TIES BETWEEN EACH PAIR AND TO THE TIE BETWEEN SAID ADJACENT UNITS. 